1. Field
The present invention relates to an organic light-emitting display device and a method of manufacturing the same.
2. Description of the Related Art
Organic light-emitting display devices have garnered much attention as next-generation display devices because of their characteristics, i.e., wide viewing angle, excellent contrast, and fast response rate. An organic light-emitting display device may include an anode electrode, a cathode electrode, and an emissive layer provided between the anode electrode and the cathode electrode and formed of an organic material. When a positive voltage and a negative voltage are applied to the anode electrode and the cathode electrode, respectively, holes from the anode electrode may move to the emissive layer through a hole injection layer and a hole transporting layer, and electrons from the cathode electrode may move to the emissive layer through an electron injection layer and an electron transporting layer. The holes and the electrons may recombine with each other in the emissive layer. Due to the recombination of the holes and the electrons, excitons may be generated. When the excitons transition from an excited state to a ground state, the emissive layer may emit light, and as a result, an image may be displayed.
The organic light-emitting display device may also include a pixel-defining layer, which has an opening through which the top of the anode electrode is exposed. An organic light-emitting layer may be formed on a part of the anode electrode exposed through the opening of the pixel-defining layer.
Some of the layers that constitute the organic light-emitting layer may be formed by a solution process. The solution process may be performed by mixing an organic material with a solvent so as to form a solution composition and adding, dropwise, the solution composition to the opening of the pixel-defining layer. Since the pixel-defining layer is lyophobic and the anode electrode is lyophilic, the solution composition may form a pinning point at a certain location on the pixel-defining layer. A pinning point is a location in a crystal that opposes the motion of dislocations. Further, the hole injection layer, the hole transporting layer, and the light-emitting layer may all have the same pinning point, and as a result, the hole injection layer and the electron transporting layer may directly contact each other at the pinning point. That is, the hole transporting layer and the electron transporting layer may be directly connected without the light-emitting layer therebetween, and thus, a leakage current may be generated.